Drugmakers, business organizations and other interest groups in the health care battle have dialed down expensive lobbying campaigns as they assess how last month's stunning Republican capture of a Senate seat from Massachusetts has altered Washington's political landscape.

Even as Democratic leaders gauge whether the health care drive can be resuscitated in Congress, lobbyists say uncertainty has been heightened by worries that didn't exist a year ago.

These include:

• Concerns about the impact of growing budget deficits.

• The ability of top Democrats to lead nervous rank-and-file lawmakers.

• A loss of momentum that shifting attention to jobs legislation could cause for the health care bill.

Some groups that backed the effort, clashing with Republicans, are even wondering whether it's time to mend fences with a resurgent GOP that could make big gains in November's congressional elections.

Absent evidence that Obama and Democratic leaders are willing to aggressively revive the health package, some question whether they should push hard for a stalled measure that may never become law if all that achieves is annoying Republicans, say lobbyists who spoke on condition of anonymity to reveal strategic thinking.

"This is a time to keep your powder dry with both sides," said Robert Laszewski, a health care consultant in Alexandria, Va. "During this lull, you want to begin to rebuild your relationships."

The geared-down lobbying is but one example of how the new year — especially Republican Scott Brown's Jan. 19 upset win for the late Sen. Edward Kennedy's Senate seat — has reshaped the health care battle, which saw half a billion dollars spent on lobbying last year.

Denied their 60-seat Senate majority that let them overcome Republican filibusters, leaders no longer know if they can muster the votes they need from rank-and-file Democrats in the House or Senate, who are now focused on their own political survival. They also don't know what a bill that could attract sufficient votes might look like — leaving health care providers, business and labor groups without details to back or oppose.

"I ran ads that were specific to bills," said R. Bruce Josten, chief lobbyist for the U.S. Chamber of Commerce, a foe of the overhaul effort and one of the biggest spenders for TV commercials until the chamber recently stopped advertising. "There's no bill right now."

None of this means lobbyists have disengaged, or changed their views on health legislation. A bill could be revived, and even a small version could have an enormous impact.

Sen. Amy Klobuchar, D-Minn., says she has been hearing from the Mayo Clinic and doctors in her state. The insurance industry has distributed reports on Capitol Hill arguing that states that require coverage for those already sick have seen rates skyrocket. AARP, representing seniors, wrote lawmakers last week saying, "We have come too far to halt progress on health care reform."

The worsening budget picture — with annual deficits now projected to remain above $700 billion indefinitely — has created a new concern for medical providers that backed the health effort and agreed to contribute billions to help finance it.

If the health bill dies and deficit reduction becomes a focus — which voters seem to want — lawmakers might enact the savings the industry groups agreed to provide for health legislation and use the money to trim budget shortfalls instead.

That would be seen as a bad deal by the hospital and pharmaceutical industries, which agreed to provide $155 billion and $80 billion respectively in 10-year savings, in exchange for supporting a health overhaul that would create millions of additional paying customers. Democrats have also targeted the insurance industry for many billions in taxes and Medicare reimbursement cuts — and may not be bashful about trying to use some of those savings to mop up red ink.

All of this follows a year in which drug companies, hospitals and other medical interests spent a record $505 million lobbying Washington — the first time any business sector exceeded half a billion dollars lobbying in one year, according to spokesman David Levinthal of the Center for Responsive Politics, a nonpartisan group that compiles such data. Omitted from that category are health insurance companies and labor, business and ideological organizations that also lobbied on the issue.

On top of that, an enormous $210 million has been spent on TV ads on the health care debate since it began a year ago, according to Evan Tracey, president of the Campaign Media Analysis Group in Arlington, Va., which tracks political advertising. That includes $100 million for a revamping and $85 million opposed, with the rest essentially neutral.

But that spending dropped sharply in the week and a half after the Massachusetts special election, when just $1 million was spent.

About $600,000 backed Obama's proposal, with leading spenders including the seniors' group AARP and the American Medical Association. Another big spender has been the Nebraska Democratic party, in defense of Sen. Ben Nelson, D-Neb., under fire for a provision that would have exclusively given his state extra federal aid for expanding Medicaid health coverage for low-income people.

Another $400,000 opposed the revamping effort, led by ads by three conservative groups: Conservatives for Patients' Rights, the Campaign for Liberty and the 60 Plus Association.

"Democrats are working on a health care bill and keeping the discussions and specifics secret. We seniors are concerned about proposals that would reduce Medicare spending," C. Everett Koop, surgeon general under Republican Presidents Ronald Reagan and George H.W. Bush, says in an ad by the 60 Plus Association. "America deserves better than this."

Notice you're not bombarded anymore by TV ads about President Barack Obama's health care overhaul plan?Drugmakers, business organizations and other interest groups in the health care battle have dialed down expensive lobbying campaigns as they assess how last month's...